修复网关没有contentype

kxs-gateway/src/main/java/com/kxs/gateway/api/filter/RequestDecoderFilter.java

@@ -67,9 +67,9 @@ public class RequestDecoderFilter extends AbstractGatewayFilterFactory<Object> {
 		return (exchange, chain) -> {
 			ServerHttpRequest request = exchange.getRequest();
 
-			String contentType = Objects.requireNonNull(request.getHeaders().getContentType()).toString();
+			MediaType contentType = request.getHeaders().getContentType();
 
-			if (FILE_TYPES.stream().anyMatch(contentType::startsWith)) {
+			if (contentType != null && FILE_TYPES.stream().anyMatch(contentType.toString()::startsWith)) {
 				// 这是一个文件请求
 				return chain.filter(exchange);
 			}